Loud-speaker



June 25, 1929.

M. R. HUTCHIS ON JP! LOUD SPEAKER Fil d June 18, 1926 2 Sheets-Sheet 1lN VENTOR ,Jr: BY

ATTORNEY J 1929. M. R. HUTCHISON, JR ,7 8,354

' LOUD SPEAKER Filed June 18, 1926 2 Shets-Sheei. 2

ENVENTOR M'llrr fl'rfgafrln'ru, J1". i

ATTORNEY onset the plates-or atented June 25 19298 UNITED sTATEs PAMILLER REESE HUTCHISQN, JE., OF LLEYVELLYN PARK,

' ASSIGNOR, BY. MESNE ASSIGNMENTS, TO ACOUSTIC PR'ZJDUGTS YORK, N. Y., ACORPORATION OF DELAWARE, v

rent easiest W'EST NEW JERSEY,

GOMPALNY, 01 NEW 1 p LGlL'D-SPEA IE3,

Application and June 18,

The present invention relates to means transmuting energy irn ulses intoaudible soiinds and further improvements in acoustic devices inrelationto sound reproducin instruments or loud-speakers, and has forone or" its objects through a novel combination of parts and scientificprinciples, to produce superior results throughout the entire musicalspectrum or scale,

It is also an object of my present invention toconstr ct a highlycompact and comparatively inexpensive, yet hardy instrument with beautyand truth of tones and overtones, and with increased power and volume 15or" sound throughout a wide range of fre quencies.

With the above objects and certain other objects also in view which willbecome apparent as the present description proceeds, and

20 the drawings are studied, my invention consists in the novel partsand "combination of parts, all ashereinafter will be more fullydescribed and particularly pointed out in the claims. r

' Referring to the accompanying drawings forming a part ofthisspecification in which like numerals designate like parts in all theviews: r

Figure 1 isia diagrammatic face view of discs which form. a part of myair confining structure.

Figure 2 is a side view inelevation of two of these plates or discsassembled with a spacing between, shown in a horizontal position.

Figure 3 is a side view in. section of two .of these plates or discsassembled with a spacing between, shown in vertical position andassociated with a telephone receiver sys- 0 teni partially in sectionand partially in elevation. The full diameters of the plates or discsare not shown, the peripheries being cut away in the view-by brokenlines.

Figure l is a side view of two of these plates or discs with a spacingbetween, shown in vertical position in elevation, and associated with apair of telephone receiver sys- I tems indicated in elevation. The fulldiameters of the plates or discs are not shown, the peripheries-beingcut away in the view by broken lines. ,1 With further reference to Fiure 1, 10,vis I a plate or disc of metal or other suitable material,wood, hard rubber, bakelite or other by suitable dies to form mutuallyembracing or nesting fiat horns It may now be seen that thesepartitioning members 12, 12, 12, 12., etc. shown curved in the presentview, confine air volumes when they are associated with a pair of spacedplates or discs, and these confined'air volumes increase systematicallyin length from the central or common opening 11 to the out er periphery.lVhereas in the present view I have shown these partitioning memberscurved according to one mathematical development it-is evident that Imay select other curves, or-even straight lines for the partitioningmembers. For best results I so find that curved partitioning membersgive longer horns of progressive lengths and consequently longer columnsof confined air of progressive lengths for resonance.

From a study of this design it is apparent 55' that my present newstructure provides a series of exceedingly compactly associated horns ofvarious lengths, from very short ones to comparatively Verylong ones,and therefore it secure very widely diii'ering resonance charcteristics'.

To be speciiic'in the identification of some of my curved horns 13 14,and 15, are the small ends of three of them mutually terminatingwithin-the common eccentric center of 05 sound propagation 11, and therespective large ends or" the horns terminating at the neriphery of theplates or discs 1314 and 15 and enclosing the curved air columns 16, 17and 18, j 1

By tracing the passageway from the-common opening 11 of the resonatinghorns 13-13 and 1l1 i and 1515 it will be ap preciated' what longcolumns of resonating air are secured andhow compactly I am an abledto-nest them, and" how cheaply I may construct them. With-furtherreference to Figure 2, 10, 10,

' disc 10, engages the threaded member are the discs or plates, 11, isthe eccentrical ly positioned opening as indicated by the dotted. lines19, and 20, and 12, 12, 12, 12,

are the partitioning members.

With further refe'rence'to Figure 3, 10, 10, are the discs or plates,12, 12, 12, 12, are

hand side of the figure when only one sound emitting device is employed,and a threaded boss 22, attached to or integral with the of thetelephone casing 24,.containing the pole piece 25, the insulated wire26, terminating in the connection ends 27 and 28. A diaphragm 30 is heldin position in a customary and standard manner in front of the polepiece 25, and in communication with the open throatway 31, which leadsto the eccentric opening, or center of sound propagation 11.

I have shown a simplified, diagrammatic telephone receiver here in theinterests of clearness, but I wish it to be clearly understood that Iwould use a standard design of telephone receiver here with customaryhardened steel permanent magnets, soft iron pole pieces, many turns offine insulated wire upon said pole pieces, a rim washer on one or bothsides of the diap ragm, and

' such other features common to telephone receiver practice as areessential to high efficiency operation when associated with radio.

reception systems.

I With further reference to Figure 4, where I have shown duplex opposedco-operating telephonereceivers in elevation, 10, 10, are the plates ordiscs providing the side members of my air confining structure, 12, 12,

12, 12, are the end edges of the partitioning members, either attachedor integral with the members 10, 10;. and 22, is the boss of thetelephone receiver on the left hand side of the drawing; 23, is thecovering member of the casing 24, and 27 and 28 are the connecting wiresleading into the casing and a continuation of the winding of theinstrument. 11 is the position of the eccentric opening, and the centerof sound wave propagation of both electro-magnetic diaphragm systems;22' is the boss of the telephone receiver on the right hand side of thedrawing; 23 is the casing member of the casing 24, and 27 and 28 are theconnecting wires leading into the casing and a contlnuation of thewinding of the instru ment. In practice, I may connect the wires 27, 28,and 27', 28 in series or in parallel to the source of sound transmutingelectrical impulses of a radio system.

With the duplex. arrangement of electromagnetic diaphragms it is clearthat I may produce an instrument of great power, since compact nest ofhorns of var ous reso-' nance characteristics -Diaphragms are ca- ,pableof highly complex vibration, and in my present structure I'provide aseries of horns of a plurality of characteristics, in an economicposition for selective resonance. To place the matter more technically,I offer a series of air columns with progressive resonance'characteristics, to the action of a diaphragm or diaphragms in highly.efiicicnt combination.

Although I have not shown a" sound reflector for backing up theinstrument described, I may of course use-one, or I may place such aninstrument as described in a cabinet with sound reflecting surfaces andthereby enhance the effects produced. Whereas I have shown theinstrument in vertical position, there are conditions under which I mayprefer to operate the instrument in a horizontal position. VVhereas' Ihave shown my fiat horns of progressing length closely nested throughour design of construction, I may resort to the construction of amultiplicity of separate units adapted to closely nest and form therebythe sounding element of'my loud speaker. Whereas I have illustrated anddescribed telephone receivers "as my sound emitting devices, I do notconfine my: self to such systems, as I may use a musical arc, or aspeaking are as sound emitting devices, or any other suitable soundemitting contrivance.

Having described my invention, I claim 1. A loud speaker of multipleresonancecharacteristics comprising a pair of spaced plates one havingan opening near the center, a plurality of walls connecting said plates,said w'alls being curved in length and extending between the edge ofsaid hole and the edges of said plates, said walls being of differentlengths to provide a plurality of externally related air columns ofdifferent lengths, and an electromagnetic diaphragm device connected tosaid opening.

2. A loud speaker of multiple resonance characteristics comprising apair of spaced circularplates each having an opening off center, aplurality of walls connecting said plates, said walls being spirallycurved in length and extending between the edges of v said holes and theedges of said plates, said walls being of different lengths to provide aplurality of externally related curved and nested air columns ofdifferent lengths, and

sound emitting devices connected to saidholes.

8. Acoustic apparatus comprising a-pair of spaced plates, a plurality ofwalls connecting said plates said walls being curved of spaced plates,

in length to provide a related air columns, dev ce 1n operative HIDIIS.

4. Acoustic apparatus having multiple resonance characteristicscomprising a pair a. pluralit' of walls connecting said plates, said wals bein curved in length and extending between the inner portion of saidplates and the outer edges thereof, said-walls being of differentlengths "to provide a plurality air columns of difi'erent lengths, andan energy transfer device associated with the inner ends of said aircolumns.

5. Acoustic apparatus 5 having multiple of externally related resonancecharacteristics comprising a pair of spaced plates, a plurality of wallsconnecting said plates, said Walls being spirally curved in length andextending inner portion of said plates and the outer edges thereof, saidwalls being of different lengths to provide a lurality of externally J.related air columns 0% different lengths, and

a common energy transfer device connected to said air columns at-theinner portion of said plates.

Signed at East. Orange, Essex and State of New Jersey, this 7th day ofJune, AL D. 1926.

' MILLERREESE HUTOHISON, JR.

between the in the county of

